The invention relates to a self-propelled, preferably single axis, motor driven work machine for moving and/or driving communal or agricultural work devices mounted on a mounting device, with a drive motor fastened to a machine or chassis, and with a hydraulically driven drive axis arranged on both sides of the machine or chassis, and protruding transversely of the direction of movement, which at each end thereof has a wheel connected to a drive shaft, and on an operating side, guide bars are provided for manually steering the work machine and for arranging an actuating member for operating and controlling the drive units formed of its hydraulic pump and hydraulic motor associated with the wheels of the drive axis. Work machines of this type are described, for example, in pre published EP 2 583 541 A1 or EP 12 405 055.0. These machines can be switched from a forward movement into a rearward movement and have actuating handles at the free ends of the cantilever-like guide bars. For adjusting or changing the speed of transport of the work machine and/or the work speed of the work devices, a manually adjustable actuating member, acting in a controlling manner on the drive motor, is attached to a guide bar. For this purpose, for example, an actuating handle or a rotating handle is used at the free end of the one guide bar, which is connected through a double Bowden cable to the drive units.
Steering of such work machines by means of guide bars requires, particularly in pathless terrain, a high manual exertion by the operating person, which causes the travel and work accuracy, as well as the work safety for persons and machine, to be impaired or reduced.